Just thought about something else. How precise do the 2 side antennas need to be? I am just trying to think about how identical I can make 2 biquads. I am guessing it won't be too much of an issue, but what if they end up being slightly "off" as far as gain etc?

So does the elevation of the plane matter with this tracker, since it only rotates?
My guess is that with an omni directional for close proximity flying along with a diversity switcher, it wouldn't matter much (assuming that for distance flying the altitude of the plane lessens the need for drastic angle changes in elevation?

Just thought about something else. How precise do the 2 side antennas need to be? I am just trying to think about how identical I can make 2 biquads. I am guessing it won't be too much of an issue, but what if they end up being slightly "off" as far as gain etc?

They don't need to be perfect. Heck, they don't even need to be that close. That's what the 100K potentiometers are for. When you calibrate this, you aim both of your antennas at the transmitter, then measure the output of you RSSI buffer (I measured the voltage at the 10uF capacitors). Adjust the potentiometers until the volages are equal.

If you are on 2.4GHz or 1.3 GHz, a "cantenna" will be easier to build than the BiQuad. I will wite the tutorial soon.

So does the elevation of the plane matter with this tracker, since it only rotates?
My guess is that with an omni directional for close proximity flying along with a diversity switcher, it wouldn't matter much (assuming that for distance flying the altitude of the plane lessens the need for drastic angle changes in elevation?

I opted to leave out tilt. To me, tilt is just one more thing to have go wrong. When an antenna tilts, it loses polarization. I opted to aim my antenna up at a 20 degree angle. This gives me a 50 degree vertical beam, which is plenty. You could also use a patch antenna for your video feed. The video antenna and the tracking antenna do not need to be the same.

There is no need for a diversity controller with this tracker. Since building this, I have retired both my Oracle and my homebrew diversity controller. This just works so well, that there is no need for the added complexity.

It's a quick demo in my driveway. I am uploading raw video since I can't get the sound to work on my video editing software. Notice that the area is a multipath nightmare, yet the tracker still has a lock on my transmitter. I had the delay timer set at 50% duty cycle.